1. Technical Field
The present invention relates to a projector.
2. Related Art
In the past, a projector provided with a light source lamp, a liquid crystal panel for modulating light beam emitted from the light source lamp in accordance with image information, and a projection lens in an enlarged manner for projecting the modulated light beam to the outside has been known.
When using a projector, there are some cases in which the projected image needs to be displayed shifted in a vertical or a horizontal direction on the screen while keeping the setting posture of the projector. In accordance with such a need, a projector equipped with a projection position adjusting device has been provided (for example, refer to JP-A-2004-205686). The projection position adjusting device is a device capable of moving the projection lens along a plane perpendicular to the projection direction. The projector equipped with such a projection position adjusting device cam display the projection image shifted in a vertical or a horizontal direction on the screen.
Specifically, the projection position adjusting device is provided with a dial knob exposed from a housing of the projector, and drives the projection lens utilizing the rotational operation of the dial knob.
When the dial knob is turned in one direction by a user, the projection position adjusting device moves the projection lens to the left, for example, along the plane perpendicular to the projection direction. Then, the projected image also moves on the screen to the left. When the dial knob is turned in the opposite direction by a user, the projection position adjusting device moves the projection lens to the right along the plane perpendicular to the projection direction. Then, the projected image also moves on the screen to the right.
As described above, the projection lens reciprocates on a moving path perpendicular to the projection direction in accordance with the rotational direction of the dial knob.
However, in the projector described in JP-A-2004-205686, the user might lose a certain projection reference position in the moving path such as the center point of the moving path while adjusting the projection position of the projector by rotating the dial knob.